//通过元素ID访问
var objById = document.getElementById("province");
console.log(typeof objById);
console.log(objById);

//通过标签访问
var objByTagName = document.getElementsByTagName("li");
console.log(typeof objByTagName);
for (var i = 0; i < objByTagName.length; i++) {
    console.log(objByTagName[i]);
}

//通过类访问
var objByClassName = document.getElementsByClassName("cur");
console.log(typeof objByClassName);
for (var i = 0; i < objByClassName.length; i++) {
    console.log(objByClassName[i]);
}

//遍历元素节点
function traversal(node){
    //node为元素节点（nodeType为1）
    if(node && node.nodeType === 1){
        console.log(node.nodeName);
    }
    //子节点
    var childNodes = node.childNodes;
    for (var i = 0; i < childNodes.length; i++) {
        var item = childNodes[i];
        if(item.nodeType === 1){
            traversal(item);
        }
    }
}
traversal(document.documentElement);

//属性节点访问
var objP = document.getElementsByTagName("p");
for (var i = 0; i < objP.length; i++) {
    var txtTitle = objP[i].getAttribute("title");
    console.log(txtTitle);
}

document.getElementById("province").setAttribute("title", "省份列表");




















